Apparatus for cleaning hose filters



Nov. 27, 1951 s. w. WALLIN 2,576,656

APPARATUS FOR CLEANING HOSE FILTERS Filed Aug. 16, 1949 4 Sheets-Sheet 1A J %WWW 322/ w AZ??? 1 J Nov. 27, 1951 s. w. WALLIN APPARATUS FORCLEANING HOSE FILTERS 4 Sheets-Sheet 2 Filed Aug. 16, 1949 mm mm L %A%Wd Nov. 27, 1951 s. w. WALLIN 2,576,656

APPARATUS FOR CLEANING HOSE FILTERS Filed Aug. 16, 1949 4 Sheets-Sheet 420 45 24 24 FIG. 9

aw/V i u MHZ???" J Patented Nov. 27, 1951 2,576,656 APPARATUS FORCLEANING HOSE FILTERS Sven Werner Wallin, Jonkoping, Sweden, as-

signor to AB Svenska holm, Sweden Fliktfabriken, Stock- ApplicationAugust 16, 1949, Serial No. 110,634 In Sweden April 21, 1948 4 Claims. I

The present invention relates to a method and arrangement for periodicalcleaning during operation of a section of the hose filter at a time byhose filters divided into section for gaseous media.

The method according to the invention is in the first placecharacterized by that the difference in pressure of the gas before andafter passing the hose filters, when the pressure of the purified gaswith a certain value is below the pressure of the not purified gas, asan impulse may affect an arrangement which actuates driving memberswhich partly send a counterdirected current of fresh air through thehose filters in one section and partly close the normal outlet forpurified gas from this section, and after a certain period of time, whenthe pressure difference is considered to be equalized, will stop thecounter-directed current of air, will open the normal outlet for thepurified ga from the section and stop the driving members because thedecreased pressure diiTerence will restore the impulse affectedarrangement to the original position. According to still anothercharacteristic feature of the method the counter-directed current of airmay partly be conducted to and utilized for the operation of a vibratorshaking the deteriorations from the hose filters of the closed section.

The arrangement for the performing of the method relates to differentsections of chambers with vertically downwards hanging hose filterswithin each section, which hose filters open out in a lower chamber,common to all the sections, which chamber is provided with inletopenings for the gaseous medium which is to be purified, which chambersections each by itself, by means of an opening in the chamber wall,open out into a box, which, by means of an opening provided with aclosing arrangement is connected with an outlet pipe common to all boxesfor the purified medium, and what is most characteristic for thisarrangement according to the invention is, that the lower chamber andthe outlet pipe for the purified medium each by means of a pipe areconnected to a pressure-difference gauge which is arranged to begin todeviate at a certain pressure difference and thus start one or moredriving members which member or members partly start an air drivingarrangement for injection of fresh air in a pressure chamber, providedwith closing members for the same number of openings from the pressurechamber as the hose filter has sections and boxes connected thereto,which open- Jugs are each connected to a box, partly start anarrangement which is arranged to open in proper turns and during acertain period of time keep open the closing members for the openingsfrom the pressure chamber mentioned to the boxes and thereafter closethese closing members again, which boxes by means of a separating Wallare divided into two compartments communicating with each other, one ofwhich by means of openings mentioned is connected to partly the hosefilter chamber section and partly the outlet pipe for purified mediumand the other compartment by means of likewise mentioned openings isconnected to the pressure chamber, in which latter compartment isdisposed a screen, possible to operate by the air from the pressurechamber and swingably journalled, which screen by means of its swingingis arranged to affect the opening and closing of the closing arrangementfor the opening between the second compartment of the box and the outletpipe for the purified medium. Other characteristic features of thearrangement according to the invention are evident from an embodimentcloser described in the following and shown in the drawings.

The invention involves the advantage that the arrangement, used for thecleaning of the hose filters, automatically is set in function and inproper turn cleans one hose filter section at a time. The cleaning ofone section is thus eifected without stopping the operation of the plantwhich is so managed that the other section or sections in the meantimetakes over the function of the section being cleaned. The cleaningproceeds during a certain period of time and is thereafter intercepted.Thereafter the other section or sections are cleaned in proper turns inthe same manner with interruptions between each cleaning. Cleaning ofone section is thus only done when it is necessary and is efiectedautomatically in such a way that the pressure diiference of the mediumbefore and after passing the filter may be the impulse which actuatesthe cleaning arrangement in section after section. Another advantage isthat the air which is led in for cleaning of the hoses in the filteralso is used for the operation of a vibrator shaking the hoses beingcleaned. The above mentioned use of the pressure difference as impulsefor actuating the cleaning arrangement furthermore involves asimplifying of the whole cleaning arrangement and makes a manual control of the arrangement unnecessary. In addition to this a specialadvantage lies in the fact that the movable parts of the arrangementhave been enclosed, that is, protected from dust, exteriordeteriorations thus not being able to disturb the operation. In certaincase the movable parts may even be immersed in an oil bath.

The invention is illustrated in one of its embodiments in theaccompanying drawings.

Figure 1 shows schematically a cross section through a gas purifyingplant.

Figure 2 is a side view of the same plant; and

Figure 3 is an end view of Figure 2 viewed from the left side.

Figure 4 shows a vertical section in a larger scale; and

Figure 5 shows ahorizontal section in a -iarger scale of the arrangementfor opening and closing of the closing members for fresh flushing airfor the sections. Figure 4 is a section of Figure 5 in line IV-IV andFigure 5 is a section of Figure 4 in line V-V. Figures 6 and 7aresections in a larger scale of the pressure difierence gauge.

Figure 6 is a section of Figure '7 in line VI--VI and Figure '7 is asection of Figure 6 in line Figures 8 and 9 are sections in a largerscale of the -box with the closing arrangement between the filterchamber and the outlet pipe. Figure 9 is a section of Figure 8 in lineIXIX. Figures '10 and 11 are sections in a larger scale of the vibratorfor the hoses.

ure 10 is a section of Figure 11 in line X-X and "Figure 11 is a sectionof Figure 10in line XI-XT.

The plant shown in Figures 1, 2 and 3 consists of thr'eecasings i, 2 and3, forming filter chamhers, separated from each other, and designated1A, 2A and 3A although only chamber in may be seen in the drawing. Thecasings l, 2 and 3 rest on and are connected to alower outlet chamber 4,the walls of which are designated 5. In casings l, 2'a-nd 3,-which areuniform, there is an upper plate?) which rests on springs 7, disposedoninteriorli'sts 8 in the casings. The plate constitutes acarryingmember for hoses s, hanging down vertically in the casings. The hoses 9are fastened to the plate 3 by forcing th'ein on annular elements 11)arranged on the lower side of the plate. Hoses 9 may be made ofmolesk'in oranyother convenient filter material. The lower ends ofthe'hoses'extend through an upper wall to the lower outlet chamber l,for this purpose being provided fwith*ho1es H, corresponding tothehose's, in which holes are arranged annularmembersfl, around whichthe lower ends "of the hoses are to be fastened. On the plate '6 isdisposed a vibrator 1-3. From the lower part of chamber 1 an "opening 44leads laterally to a box or outlet chamber [5. 1n the bottom of theinlet "chamber A is disposed an endless screw it which servesthe purposeof transporting away fallen "down deteriorations from chamber d, the'deteriorations being separated from the medium which is to be purified.'The medium is introduced into the chamber 4 through -a pipe 'ii and"from there rises in the hoses in all the casings, "is filtered by thehoses and enters the chambers "IA, 2A and-3A from which the purifiedmedium escapes throughopening's M to boxes. or outlet chambers 15. Theboxes or chambers 15 are by means 'of an interior separating wall 15a,into two compartments l9 and 20, communicating witheaoh other through anaperture or passage i'8. See especially Figures 8 and 9 showing the boxin a larger scale. Compartment 2! has two openings one ofwhi'ch isconnected to open- 'ing 14 and the other'one, 2|, is connected to anoutlet pipe or duct 22 for purified medium, the outlet pipe being commonto all boxes. Openh1g2 I is provided with "avalve '23 supportedby I twoarms 24 fixedly arranged on an axis 2'5, rotatably journalled in the boxIS, the axis furthermore supporting a screen 26, fixedly attached to androtatable with the axis 25. The valve 23 consists of a plate, which bymeans of screws 27, nuts 28 and springs 29 is resiliently journalled inanother plate 33, fixedly fastened to the arms 24. The valve 23 and thescreen 25, are shown in Figure 8 in partly a full drawn closed positionwith reference to the valve, and partly a dash-dotted open position.

The compartment i9 is provided with the apertime 18 previouslymentioned, constituting a communication between the compartments l9 and28, an opening 3i connected to a pipe 32 and an opening 33 connected toa pipe 3 1 leading to the vibrator E3. The boxes i5 rest by means of afoot part 35 on and are fixedly fastened to the outletpipe 22 with whichthe foot part communicates.

From the lower chamber 3 a pipe 33 and from the outlet pipe 22 anotherpipe 3"? leads to a pressure difference gauge 33. This consists of ahousing separated in two compartments 4% and 4'! by means of a verticalpartition 35 (see Figures ti and 7 which compartments both are connectedwith the atmosphere by means of an opening 43 closed with-a lid #32. Inthe housing in the drawing.

of the pressure gauge 38 is a shaft M, supporting the wings =45 and '43,rotatably journalled. By the rotation of the shaft the wings '45, "ismove at a very little distance from the wall or the housing. The shaftis provided with a threaded -projection i? on which a weight 58 isdisplace'abie by means of threads and a locking nut 49 and possible tolock in order to change the equilibrium of the wings 5346. On the shaftat is furthermore fixedly arranged a mercury switch 58 the connections5! and 52 of which are taken through holes in the wall of the pressuregauge and lead to one or more electrical -motors,

described in the following.

A housing is designated 53 (seespeciallyFi'gures 4 and 5) which isdivided into two chambers completely separated irom each other, onepressure "chamber as and one motor chamber 55. The partition wallbetween the chambers is designated '56. Chamber 54 is provided with anopening 51 which is connected to a pressure um is, driven by anelectrical motor '59 and blowing compressed fresh air into the chamber'55. The starting and stopping of this motor 'is regulated by means ofthe mercury switch 58, the connections of which lead to the startingdevice or themot'or although this is not especially shown From thepressure chamber pipes 32 lead to boxes 15, one pipe 3 2 120 each boxIS. The ends of the pipes 32 opening out in the pressure chamber areprovided with control valves in the shape of adisc 5d, rotatablyjournalled on an arm iii around a pivot 62. Arm 3| extends through anopening 63 in the partition wall 56 and forms a tight closure to thiswall by means of metal bellows 3'4 surrounding the arm, the metalbellows being only slightly sensitive to'pressure from'chamber butletting -the "arm freely rotate around a shaft 65 oom mon to all arms 3I, shaft 65 being rotat'ably joui' nalledin chamber 55. Arm 6 5 istwo-armed and one end supports the valve 69 and-the oth'erend supports aroller 56, rotatabl'y arranged around a pivot 61. The rollers 36 of thearms =61 make contact against a drum H providedw-ith cams 68, 69 andill, the drum being rotatably 50in"- 'nal-led a'r'ou'nd shaft 12 in thechamber 55, axis 12 being journalled in bearings 13 and 14. The drum isprovided with a toothed wheel 75, driven by an endless chain :6 from thechain drive i! belonging to the gearing l8 driven by an electricalmotorlil. The starting device of this motor is also connected to themercury switch 59 as is evident from Figure l and the motor is startedandstopped by means of the mercury switch.

1 The screen 26 described in connection with Figures 8 and 9 is formedaccording to the walls of the housing but leaves a small distance freebetween the contour of the screen and the wall oi the housing.

The vibrator consists of a housing with an inlet 80 for compressed airand an outlet iii. In the housing of the vibrator as shaft $2 is fixedlyarrangedand on this shaft two bearings 33 and 3d are, mounted,supporting a wing 85, set into motion around axis 82 by compressed airthus generating vibrations by means of the compression impacts.

The arrangement according to the invention functions in the followingway.

The medium to be purified, enters into the inlet chamber 4 through pipe11, from which chamber it rises in the hoses 9 and penetrates the wallsof the hoses and enters into chamber IA and escapes through the openingit in a purified state. Conditions are analogous for all casings 1,2,and 3. If the hose filters are newly inserted all the valves 23 willassume the open position shown with dash-dotted lines in Figure Thepurified medium then continues from openlit ing 14 through compartmentand out through opening 2! and into and away through outlet pipe 22.

. As long as the pores of the hose filters are not closed bydeteriorations the pressure in the let chamber 4 and in the outlet pipe22 is substantially the same. When one or more of the hoses of thefilter sections begin to be plugged the pressure in the outlet pipe 22will be lower than the pressure in the inlet chamber 4 which results ina pressure diiference between the average pressures in pipes 36 and 37which difference successively will increase in value. ence in pressureis registered by the wings i5 and 46 which by means of the weight 43have been adjusted so that the wings balance each other at substantiallythe same pressure in the pipes 36 and 31, but are moved from thisposition by counterclockwise rotation of the shaft 44 owing to theefiect of the arising pressure difference, so that on reaching apredetermined pressure difference the shaft 44 has rotated enough sothat the mercury switch 5B, which from the beginning I has been open,will close the circuit to the motors 59 and ill. The closing of thecircuit from the supply lines A through the main switch A starts thesemotors. Motor 59 runs the pump 58 blowing compressed air into chamber54, all the valves 60 of which have been closed in the meantime. As themotor i9 simultaneously runs the gearing l8 and the pinion H and thelatter wheel runs the chain 18 and thus the toothed wheel 15, the drumll will also be set into motion, causing the cam 68 to lift one end ofarm 6! and during a certain period of time keeps it lifted up andthereafter to lower it again. The lifting of the arm causes a loweringof the other end, thus opening the control valve on the pipe 32 andletting compressed air pass the opening and enter compartment [9 in box15. Owing to the effect of the air pressure the screen 2'5 will rotateshaft 25 and thus arms 24 clockwise resulting in that the valve 23 willclose the opening 2|. Continued flowing The diff erin of air intochamber compartment '15 results in this air passing through the openingsbetween screen 26 and the interior walls of the chamber compartment andcontinues through opening it into chamber compartment 28 and from thereinto chamber IA, through the hose filters in opposite direction to themedium which is to be purified and enters into the lower chamber 4 afterhaving passed the hoses and then cleaned them from adheringdeteriorations which fall down into chamber 4 and are transported awayby means of conveyor Hi. When screen 26 has moved sufliciently to clearthe opening 33 01 pipe 34 the compressed air flows through the pipe tovibrator l3 and runs said vibrator thereby vibrating plate 6 whichshakes the hoses and facilitates the cleaning of the hoses fromdeteriorations. After cleaning the hoses of one section in this mannerdurin a certain period of time, the pressure difference between thepressure in pipes 36 and 3'! will drop and the wings will return to theoriginal position by means of weight 48 thus causing the mercury switchto break the current to the motors which stop. In the meantime cam 68 ofthe drum H has passed roller and arm 6| has been lowered, i. e. valve G8has closed pipe 32 and stopped the communication between the compressedair chamber 54 and box 55. Fresh air then beings to enter box IE againand opens the valve 23, which furthermore on account of its own weightreturns to the position with free opening 2!, shown in Figure 8 withdash-dotted lines. The plant now works normally again without cleaningof the hoses until a new pressure difference will appear, actuating thecleaning mechanism again, but this time it is the next section of thefilter which is to be cleaned, which procedure thereafter is repeated.

Having now described my invention, what I claim as new, and desire tosecure by United States Letters Patent, is:

1. In filter apparatus comprising a plurality of filter casings eachhaving a plurality of vertically extending filter hoses in each thereofand an inlet chamber for the mechanism to be purified underlying saidfilter casings and arranged so that the medium to be filtered enteringsaid inlet chamber is caused to pass upwardly into said filter hoses andthen outwardly through the lat ter into said filter casings, meansdefining an outlet chamber for each casing for the purified medium, anoutlet duct communicatim with each outlet chamber, normally open valvemeans for closing-oil communication between said outlet duct and saidoutlet chambers, actuating means for said valve means in each outletchamber operable in response to a predetermined gaseous fluid pressureto close said valve and simultaneously cause said pressure fluid to flowfrom said outlet chambers into said filter casings and inwardly throughthe hose filters therein to clean the same, a source of gaseous pressurefluid, a connection from said source to each outlet chamher, a normallyclosed control valve for each said connection, cam means constructed toopen said control valves one at a time in predetermined sequence, andmeans responsive to a predetermined differential between the inletchamber pressure and the outlet chamber pressure operable to actuatesaid cam means thereby to open said control valves in predeterminedsequence and cause the gaseous pressure fluid to flow to the outletchambers in accordance with the quential opening of said control valves.

2. In filter apparatus comprising a plurality of filter casings eachhaving a plurality ofvertically extending filter hoses in each thereofand an inlet chamber for the mechanism to be purified underlying saidfilter casings and arranged so that the medium to be filtered enteringsaid inlet chamber is caused to pass upwardly into said filter hoses andthen outwardly through the latter into said filter casings, meansdefining an outlet chamber for each casing for the purified medium, anoutlet duct communicating with each outlet chamber, normally open valvemeans for closingoff communication between said outlet duct and saidoutlet chambers, actuating means for said valve means in each outletchamber operable in response to a predetermii'ied gaseous fluid pressureto close said valve and simultaneously cause said pressure fluid to flowfrom said outlet chambers into said filter casings and inwardly throughthe hose filters therein to clean the same, a source of gaseous pressurefluid including a pump, a connection from said source to each outletcham ber, a normally closed control valve for'each said connection, cammeans constructed to open said control valves one at a time inpredetermined sequence, and means responsive to a predetermineddifferential between the inlet chamber pressure and the outlet chamberpressure operable to drive said pump and to actuate said cam meansthereby to open said control valves in predetermined. sequence and causethe gaseous pressure fluid to flow to the outlet chambers n accordancewith the sequential opening of said control valves.

3. In filter apparatus comprising a filter casing having. a plurality ofvertically extending filter.

hoses therein in spaced relationship and an inlet chamber for a mediumto be purified underlying said filter casing and arranged so that themedium to be filtered is caused to pass upwardly into said filterhoses'and then outwardly through the latter into said filter casing,means defining an outlet chamber for the purified medium communicatingwith said casing, an. outlet duct communicating with said outletchamber, normally open valve means for closing-off communication betweensaid outlet duct and said outlet chamber, actuating means for said valvemeans in the outlet chamber operable in response to a predeterminedfiuid pressure to close said valve and simultaneously cause saidpressure fluid to i flow from said outlet chamber into said filtercasing and inwardly through the hose filter to clean the same, mechanismresponsive to a predetermined differential between the inlet cham-- berpressure and the outlet chamber pressure operable, to discharge into theoutlet chamber a gaseous fluid at said predetermined pressure thereby tooperate said valve closing means and cause the pressure fluid to now tosaid filter a 8 casings, said mechanism being aut matically renderedinoperative when the pressure difieren tial falls below saidpredetermined value, a gasdriven vibrator connected to the hose filters.for shaking them, and a connection to said vibrator from the outletchamber for conducting a por tion of the gaseous fluid discharged intosaidout let chamber to. said vibrator to drive the same.

4. In filter apparatus comprising a plurality of filter casings eachhaving a plurality of vertically extending filter hoses in each thereofand anin let chamber for the mechanism to be purified underlying saidfilter casings and arranged so. that the medium to be filtered enteringsaid inlet chamber is caused to pass upwardly intosai'd filter hoses andthen outwardly through the latter into said filter casings, meansdefining an outlet chamber for each casing for the purified medium, anoutlet duct communicating with each outlet chamber, normally open valvemeans for closingoiT communication between said outlet duct and saidoutlet chambers, actuating means for said valve means in each outletchamber operablein response to a predetermined gaseous fluid pressure toclose said valve and simultaneously cause said pressure fluid to flowfrom said outlet chainbers into said filter casings and inwardly throughthe hose filters therein to clean the same; mechanism responsiveto apredetermined differential between the inlet chamber pressure and outletduct pressure operable to discharge into saidoutlet chambers one at atime a gaseous fiuid at said predetermined pressure thereby to operatesaid valve closing means in said one chamber and cause" the' pressurefiuid to flow to its associated filter casing, said mechanism beingautomatically rendered inoperative when the pressure difie'rential fallsbelow said predetermined value; a gas driven vibrator connected to thehose filters in" each casing for shaking them, and a conrie'ctio'rr tosaid vibrator from the associated outlet chain's ber for conducting aportion of the gaseousfluid discharged into said outlet chamber to saidvibrator to drive the same.

SVEN' WERNER WALLIN;

REFERENCES, CITED The following references are. of record in the" fileof this patent: V

UNITED STATES. PATENTS" Number Name Date- 1",638,067 Szekely Aug. 9,192? 1,784,339 Clasen" etal'. Dec; 9; I930 1,806,513 Straus-ScharinaMay' 19,- 1931 1,974,952 Eiben Sept. 25, 1934f 2,276,805 Tolman Mar.17,1942 2368,78"? Skinner Feb. -6, i945

